The definition of “building sewer” as adopted by the Uniform Plumbing Code shall be amended to mean the following: the building sewer for which the property owner is responsible for maintaining shall be that portion of the line beginning two feet outside the outer foundation wall of the structure to the sanitary sewer main. (Ord. 947 §1 (part), 1992; Ord. 875 §5 (part), 1990).